WO1998037255A1

WO1998037255A1 - Transparent conductive film, sputtering target and substrate equipped with the transparent conductive film

Info

Publication number: WO1998037255A1
Application number: PCT/JP1998/000708
Authority: WO
Inventors: Akira Mitsui
Original assignee: Asahi Glass Company Ltd.
Priority date: 1997-02-21
Filing date: 1998-02-20
Publication date: 1998-08-27
Also published as: EP1004687B1; JP3925977B2; JP2002012964A; DE69820639D1; EP1004687A1; EP1004687A4; DE69820639T2

Abstract

A tin oxide type transparent conductive film containing gallium and indium, wherein, when gallium, indium and tin are converted into Ga2O3, In2O3 and SnO2, respectively, the gallium content as converted into Ga2O3 is 0.1 to 30 mol% to the sum of Ga2O3, In2O3 and SnO2 and the indium content as converted into In2O3 is 0.1 to 30 mol%. This invention provides also a sputtering target and a substrate equipped with a transparent conductive film. The transparent conductive film has high chemical resistance and abrasion resistance, and is useful as a high-durability antistatic film. The target of this invention is compact and can be sputtered by stable discharge.

Description

Specification

Transparent conductive film, sputtering target and substrate with transparent conductive film

Technical field

The present invention relates to a transparent conductive film, a sputtering target, and a substrate with a transparent conductive film.

Background art

Transparent conductive films have both high visible light transmittance and high conductivity, and are used as transparent electrodes for display devices such as liquid crystal display devices and plasma light-emitting devices, transparent electrodes for solar cells, heat ray reflective films for automotive and architectural glass, and CRT. It is widely used as an antistatic film, or as a transparent heating element for various anti-fog applications such as freezing and refrigeration showcases.

Conventionally, an ITO (tin-doped indium oxide) film is mainly used as a transparent conductive film because a low-resistance film can be easily obtained. In particular, ITO films are widely used as electrodes for display elements. In addition, a low-cost transparent conductive film of zinc oxide and a low-cost transparent transparent conductive film of tin oxide are also known.

As a problem of the conventional transparent conductive film material, ITO, which is a main component of ITO, is expensive, which is an obstacle to cost reduction. Zinc oxide-based transparent conductive films have low chemical resistance to acids and alkalis. Therefore, it is difficult to apply the zinc oxide-based transparent conductive film to industrial products such as display elements.

The tin oxide-based transparent conductive film has extremely excellent chemical resistance as compared with the ITO film and the zinc oxide-based transparent conductive film.

Tin oxide is produced by spraying or CVD as an industrial production method, but it is difficult to form a uniform film thickness. In addition, chlorine and hydrogen chloride were generated during film formation, and there was a problem of environmental pollution due to these exhaust gases (or effluents). While the tin oxide-based transparent conductive film is useful, it has the various problems described above. Further, since the tin oxide-based transparent conductive film is crystalline, there is a problem that scratch resistance is low. The reason why the scratch resistance is low is considered to be that fine irregularities formed during crystal growth are present on the surface of the film, and these are clogged.

By the way, in general, as a large-area film forming method, a sputtering method that can easily obtain a uniform thin film and has low environmental pollution is suitable. Sputtering methods can be broadly classified into radio frequency (RF) sputtering methods that use a high-frequency power supply, and direct current (DC) sputtering methods that use a DC power supply. The RF sputtering method is excellent in that an electrically insulating material can be used for the target, but a high-frequency power supply is expensive, has a complicated structure, and is not preferable for forming a large-area film. .

DC sputtering method, data one rodents preparative material is limited force in highly conductive ^material?, Easy to operate because the device structure is the use of a simple DC power source. As the industrial film forming method, the DC sputtering method is preferable. Japanese Patent Application Laid-Open No. 1-97315 proposes a method of forming a tin oxide conductive film by a sputtering method, but describes only an RF sputtering method and does not describe a DC sputtering method. . Also, film resistivity also only such have obtained 8 X 1 0- ³ Ω cm or more relatively high-resistance film Les,

Further, in _{JP-7- 33 50 3 0, ln 2} 0 3, Z n O, S N_〇 _2, and G a ₂ 0 ₃ 1 kind selected Ri by the group consisting of or a transparent conductive consisting more Oxides have been proposed. However, there is no specific description of the composite oxide containing tin oxide.

In addition, Japanese Patent Application Laid-Open No. 4-272612 proposes a gallium-containing ITO film, in which ^s and indium oxide are the main components, and tin oxide is not the main component.

The present invention solves the above-mentioned disadvantages of the prior art, and provides a tin oxide-based transparent conductive film having low resistance and high abrasion resistance, a method for producing the same, and a sputtering target for forming the tin oxide-based transparent conductive film. The purpose is to provide

Disclosure of the invention

The present invention is a transparent conductive film of tin oxide containing a Gariumu and Lee indium, converting the gully um to G a ₂ 0 _3, by converting the Lee indium to I n ₂ 0 _3, tin S n

0 ₂ when converted into, based on the total amount of the G a ₂ 0 ₃ and I n ₂ 0 ₃ and S n 0 _2, the gas re um containing 0.1 to 3 0 mol% G a ₂ 0 in terms of And indium is In ₂

0 equivalent to ₃ 0.1 to 3 0 mol% trivial drawings to provide a transparent conductive film, characterized in containing explained

FIG. 1 is an X-ray diffraction pattern of a film in Example 2 which is an example of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

The same applies to the definition of the content ratios of gallium and indium. If the content ratio of either gallium or indium is less than 0.1 mol% in terms of oxide, the specific resistance of the film becomes high and the film becomes crystalline. When the content of any one of them is more than 30 mol% in terms of oxide, the specific resistance of the film increases.

Since good Ri low resistance film can be obtained, the content of the gully um is from 1 1 to 5 mole ^_0/0 G a ₂ 0 ₃ in terms of the content ratio of Katsui indium is at I n ₂ 0 ₃ in terms of 1 is preferably 1 to 5 mol ^_0/0.

Further, it is preferable to contain antimony and phosphorus or tellurium because a film with lower resistance can be obtained. Antimony is a S b ₂ 0 ₅ terms in tellurium T E_〇 ₂ terms, G a ₂ 0 ₃ and I n ₂ 0 ₃ and S with respect to the total amount of n0 _2, 0. 0 1 in total

Preferably, it is contained in the range of 10 to 10 mol%. 1 is in the 0 mole ^_0/0 good More than the resistance that a high trend. If the amount is less than 0.01 mol%, the effect of lowering the resistance is small. The same applies to the definition of the content ratio of antimony and Z or tellurium. In the transparent conductive film of the present invention, in order to further improve the abrasion resistance, a group consisting of group 3 (including lanthanide and excluding actinide), group 4 and group 5 in the long-period periodic table. It is preferable to contain at least one metal selected from the following (hereinafter, referred to as a Group 3 to 5 metal).

The Group 3 to 5 metal is preferably contained in the film in the form of an oxide (hereinafter, referred to as Group 3 to 5 metal oxide). 3-5 group metal oxide, S n0 ₂ and I n ₂ 0 ₃ and G a

Based on the total amount of the ₂ 0 _3, are preferably 0.0 5-5 mole ^_0/0 containing in total

. If the amount is less than 0.05 mol%, the effect of further improving the scratch resistance is small. On the other hand, if it exceeds 5 mol%, the specific resistance of the film becomes high.

In calculating the content ratio of the Group 3 to 5 metal oxide, it is calculated based on an oxide (described later) exemplified as the Group 3 to 5 metal oxide. The same applies to the definition of the content ratio of Group 3 to 5 metal oxides.

Group 3 includes Sc, Y, and Lanyu noise (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu ). In particular, Y, La, Ce, Pr, and Nd are relatively inexpensive and have high chemical resistance. preferable.

The oxide of Group 3 _{_{metals, S c 2 0 3, Y}} 2 0 3, L a 2 0 3, C e 0 2, P r 6 0] 1, N d 2 0 3, Pm 2 0 3, Sm _{_{_{2 0 3, E u 2 0}}} 3, G d 2 0 3, T b 4 0 7, D y 2 0 3, H o 2 0 3, Er 2 0 3, Tm 2 0: i, Yb 2 〇 _3, L u ₂ 0 _3, and the like.

Group 4 includes Ti, Zr, and Hf. In particular, Ti and Zr are preferable because they are relatively inexpensive and have high chemical resistance.

The oxide of Group 4 _{metal, T i 0 2, Z r} 0 2, H f 0 2 and the like.

Group 5 includes V, Nb, and Ta. In particular, Nb and Ta are preferred because they are relatively inexpensive and have high chemical resistance.

Oxides of Group 5 _{_{_{metals, V 2 0 5, Nb 2}}} 0 5, T a 2 0 5 and the like.

The specific resistance of the transparent conductive film of the present invention is preferably 1 Ωcm or less from a practical viewpoint. In contrast, if the resistivity is too small, since the film thickness required to obtain a predetermined resistance value is too small, since the continuous film difficulty to obtain Kunar, resistivity 1 0- ⁵ Ω cm or more Preferably, there is.

The visible light transmittance of the transparent conductive film of the present invention is preferably 70% or more from a practical viewpoint.

The present invention also provides a sputter phosphorus Gutage' bets tin oxide containing gallium and indium, converting the gallium G a ₂ 0 _3, by converting the indium I n ₂ 0, tin S n 0 ₂ when converted into, based on the total amount of the G a ₂ 0 ₃ and I n ₂ 0 ₃ and S n 0 _2, gallium containing from 0.1 to 3 0 mol% in G a ₂ 0 ₃ in terms of, or the final indium provides Supattari Ngutage' you want to, characterized in that it contains 0.1 to 3 0 mol% in I eta 0 ₃ terms.

If the content ratio of either gallium or indium is less than 0.1 mol% in terms of oxide, the specific resistance of the formed film becomes high, and the film becomes crystalline. Furthermore, had the content of the Zureka often Ri by 3 0 mol% in terms of oxide, since the film obtained resistivity of the film is high is lower resistance, the content of the gully um is G a ₂ 0 ₃ conversion is 1 to 1 5 mole ^_0/0 by calculation, and the content of indium 1 in I n ₂ 0 ₃ in terms of

1 is preferably 5 mol ^_0/0. Further, the target of the present invention preferably contains antimony and Z or tellurium, since a film with lower resistance can be obtained. Antimony is a S b ₂ 〇 ₅ conversion, tellurium at T e 0 ₂ terms, the. Total amount of S b ₂ 0 ₅ and T e 0 ₂ and G a ₂ 0 ₃ and I n ₂ 0 ₃ and S n0 ₂ On the other hand, the total amount is preferably in the range of 0.01 to 10 mol. If the content is more than 10 mol%, the resistance of the target and the obtained film tends to increase. In addition, the target density (density) tends to decrease, and the discharge during sputtering tends to be unstable. If the amount is less than 0.01 mol%, the effect of lowering the resistance is small.

In order to enable stable sputtering, the relative density of the target is preferably about 80% or more, that is, the target density is preferably 5.5 gZc c or more.

In addition, since a higher density target can be obtained, it is preferable to contain the above-described Group 3 to 5 metal. The group 3 to 5 metal is preferably contained in the target in the form of an oxide (that is, a group 3 to 5 metal oxide).

Specific examples of the Group 3 to 5 metal and the Group 3 to 5 metal oxide are the same as described above.

3-5 group metal oxide, based on the total amount of the S n0 ₂ and I n ₂ 0 ₃ and G a ₂ 0 _3, it is preferable to 0.0 5-5 mole ⁰ / o containing in total. If it is less than 0.05 mol% or more than 5 mol%, the target density tends to decrease.

For stable sputtering discharge, the specific resistance of the sputtering target is preferably 1 Ωcm or less.

Gallium in the target is preferably present in an oxide state or a solid solution state. Here, the oxide state, tri-state gallium oxide (G a ₂ 0 ₃₎ or oxide Lee indium (I n ₂ 0 ₃₎ and Z or a composite oxide of tin oxide (S n 0 ₂₎ Means the state. A solid solution state means a state of tin oxide gallium is solid-solved (S n◦ ") and Z or oxidation Injiumu which Gariumu is solid-solved (I n ₂ 0 _3). In particular, gallium large that Part is S n 0 ₂ or I n ₂ 0

_: It is preferable that it exists as a solid solution in _ί .

It is preferable that indium in the evening get exist in an oxide state or a solid solution state. Here, the oxide state is defined as I n, 0, (S ηθ, or G a 0 3 is meant the state of the composite oxide of the state of solid solution or may be) or S n 0 ₂ and / or G a ₂ 0 _3,. A solid solution state, S n 0 ₂ and Roh or Lee indium which Lee indium is solid-solved is meant G a ₂ 0 ₃ was dissolved. In particular, indium is present in that state in which most of a solid solution to _{_{I n 2 0 3 (S n}} 0 2 or G a ₂ 0 ₃ is good even if dissolved Les) state or S n 0 ₂ of Preferably

It is preferable that the gallium and the alloy exist in an oxide state or a solid solution state in that the transparent conductive film can be easily produced. However, even if it is contained in a state other than the oxide state or the solid solution state to the extent that there is no problem, for example, metal, carbide, nitride, etc., the object of the present invention is not spoiled.

If Supattari Ngutage' gallium in bets and Injiumu are present in oxide state, arbitrary preferred that the maximum particle size of the crystal grains of the oxide is less 2 0 0 Λ _m. The presence of oxide particles having a maximum particle size of more than 200 m is not preferable because sputtering discharge becomes unstable. The average particle size is preferably 0.01 m or more from the viewpoint of handling of the powder and moldability. If the average particle size is more than 50 m, the sinterability is reduced, and it becomes difficult to obtain a dense sintered body. Therefore, the average particle size is preferably 50 m or less.

The target of the present invention may contain other components to such an extent that the object and effects of the present invention are not impaired, but it is desirable to keep the target as small as possible.

The composition of the film approximately matches the composition of the target. However, the composition of the film may deviate from the target composition depending on the sputtering conditions during film formation.

The target of the present invention can be produced by a method for producing ceramics in general, such as a normal pressure sintering method and a hot press method.

In the case of normal pressure sintering, firing at a high temperature is necessary. At high temperatures, oxides are decomposed and easily evaporated, and the target is difficult to densify, so it contains oxygen such as air It is preferable to perform sintering in an atmosphere. For example, normal pressure sintering is performed in air at a temperature of 130 to 160.

In the case of hot pressing, sintering can be performed at a relatively low temperature, so that an oxidizing atmosphere (an atmosphere containing an oxidizing gas) and a non-oxidizing atmosphere (an atmosphere containing no oxidizing gas) can be used. T / JP9 / 00708

7 may be used, but in the case of a hot press, carbon is generally used for the mold material, and it is preferable to perform the treatment in a non-oxidizing atmosphere from the viewpoint of preventing oxidation of the mold material. For example, hot press at 800 to 110 ° C in a non-oxidizing atmosphere.

In the case of the normal-pressure sintering in the air, a target can be produced, for example, as follows. G a ₂ 0 ₃ powder was prepared I n ₂ 0 ₃ powder and S n 0 ₂ powder, mixing these powders in a predetermined ratio. At this time, water is used as a dispersant and mixed by a wet ball mill method. Next, the powder is dried and then filled in a rubber mold, and is subjected to pressure molding with a cold isostatic press (CIP) at a pressure of 1500 kg Zcm ² . Then in the air 1

It is kept at a temperature of 500 ° C. for 2 hours and fired to obtain a sintered body. The sintered body is machined to a predetermined size to produce a target material. The target material is metal-bonded to a backing plate made of a metal such as copper to produce a target. In the case of a hot press, a target can be produced, for example, as follows. After mixing and drying the raw material powders as in the case of normal pressure sintering, the powder is filled into a carbon hot-press die, and the powder is filled into argon (Ar) 900. It is kept at a temperature of C and a pressure of 300 kgcm ² for 2 hours and sintered. Thereafter, the same machining and metal bonding as in normal pressure sintering is performed to produce the target.

In addition, the target of the present invention has a high conductivity, so that a large-area film can be formed, and the target can sufficiently cope with the DC sputtering method in which the film forming speed is high, and the RF sputtering can be performed. Any sputtering method such as a sputtering method can be used.

The transparent conductive film of the present invention preferably has a geometric film thickness (hereinafter simply referred to as a film thickness) in the range of 3 nm to 5 m. If the film thickness exceeds 5, the film formation time becomes longer and the cost increases. When the film thickness is less than 3 nm, the specific resistance increases. In particular, the range of 3 to 300 nm is preferable.

The present invention also provides a method for producing a transparent conductive film containing tin oxide as a main component on a substrate by a sputtering method, wherein the sputtering target is used as the sputtering target. A method for producing a transparent conductive film is provided.

In the present invention, it is preferable to perform sputtering in an oxidizing atmosphere. The oxidizing atmosphere is an atmosphere containing an oxidizing gas. The oxidizing gas means an oxygen atom-containing gas such as 0 _{_₂} H ₂ 0 CO C0 ₂

. Oxidizing gas concentration greatly affects film properties such as film conductivity and light transmittance

. Therefore, it is necessary to optimize the concentration of the oxidizing gas under the conditions to be used, such as the apparatus, the substrate temperature, and the sputtering pressure.

Ar-0 as the sputtering gas. System or A r _ C 0 ₂ system, making the transparent low-resistance film, preferably in that easily controlling the composition of the gas. Particularly A r - C0 preferable in _{that 2} system is more controllability is excellent.

In A r _0 ₂ gas system, since the transparent low resistance film can be obtained, 0 ₂ concentration is preferably 5 2 5 vol%. If it is less than 5% by volume, the film will be colored yellow and the resistance of the film will be high. If the content is more than 25% by volume, the resistance of the film increases.

In the A r- C0 ₂ gas system, since the transparent low resistance film can be obtained,

C0 ₂ concentration is preferably 1 0 5 0 vol ^_0/0. 1 0 vol ^_0/0 good small and film is colored yellow is, the resistance of the membrane becomes higher. If it exceeds 50% by volume, the resistance of the film increases.

However, depending on the application, a colored film or high resistance may be required, and the concentration is not limited to the above.

As the sputtering method, any sputtering method such as a DC sputtering method and an RF sputtering method can be used. In particular, the DC sputtering method having excellent industrial productivity is preferable.

The transparent conductive film of the present invention can be manufactured as follows. Using a magnetron DC Supattari ring device, using the target described above, 1 a chamber 0 1 0- ⁴ T

Vacuum to 0 rr. Since the pressure in Chiyanba is 1 0- ⁴ T 0 rr affected remaining residual moisture in a vacuum and higher, the resistance controlling difficulty Kunar. In addition, since it takes time to vacuum and low Ri by 1 0- ⁷ T 0 rr pressure in the chamber, productivity is evil Kunar. The power density during sputtering (the value obtained by dividing the input power by the area of the target surface) is preferably 110 W / cm ² . lWZc m ² is smaller than the discharge is not stable. If it is higher than 1 OW / cm ² , the possibility that the target is cracked by the generated heat increases.

The sputtering pressure is preferably from 10 to 10 Trr. Ten- ^{If it is} smaller than 4T orr or higher than 10—orr, the discharge tends to be unstable.

Examples of a substrate on which a film is formed include glass, ceramics, plastics, and metal. The substrate temperature during film formation is not particularly limited, but is preferably 300 ° C. or lower from the viewpoint that an amorphous film can be easily obtained.

The temperature of the substrate may be about room temperature when no intentional heating is performed, that is, about room temperature. After the film is formed, the substrate may be post-heated (heat treated). The heat treatment is preferably performed at 60 to 400 ° C. in the air. If the temperature is lower than 60 ° C, the effects of lowering the resistance by heat treatment and imparting resistance stability are small. If it is higher than 400 ° C, the resistance will be higher. Also, heat treatment can be performed in a non-oxidizing atmosphere (for example, Ar or nitrogen). The temperature at this time is preferably from 60 to 600 ° C. If the temperature is lower than 60 ° C, the effects of lowering the resistance and providing resistance stability by heat treatment are small. If the temperature is higher than 600 ° C, the film is reduced and tends to be colored.

In order to obtain high scratch resistance, the film is preferably amorphous. However, even if it is slightly crystallized, the adhesive strength of the crystal grain boundary of the transparent conductive film of the present invention is high, and high scratch resistance can be obtained.

Further, the transparent conductive film of the present invention is extremely excellent in acid resistance and alkali resistance.

It is hardly affected by strong acids and strong alkalis, and there is almost no change in film resistance. Also

It is hardly affected by hydrofluoric acid (HF) aqueous solution, and there is almost no change in film resistance. Furthermore, it has the same high corrosion resistance against a fluoride gas such as CF ₄

The present invention provides a substrate with a transparent conductive film, wherein a tin oxide-based transparent conductive film containing gallium and indium is formed on the substrate. This substrate with a transparent conductive film can be used as a transparent surface heater or an antistatic article. Also, it can be used for antistatic wafer transport chucks for semiconductor manufacturing.

The transparent surface heater can also be obtained by directly coating the transparent conductive film of the present invention on a glass or plastic film. The thickness is preferably from 10 to 300 nm from the viewpoint of the resistance value. Antistatic articles can also be obtained by directly coating the transparent conductive film of the present invention on glass or plastic film. The thickness is preferably 3 to 100 nm from the viewpoint of the resistance value.

Further, the wafer transporting chuck with antistatic for semiconductor production can also be obtained by directly coating the transparent conductive film of the present invention on a ceramics chuck. The thickness is preferably from 3 to 300 nm from the viewpoint of the resistance value.

In the substrate with a transparent conductive film of the present invention, one or more undercoat films can be provided between the transparent conductive film layer and the substrate for the purpose of adjusting the appearance. Alternatively, by providing one or more layers of an overcoat film on the transparent conductive film, the transmission / reflection color tone and the visible light reflectance can be adjusted by utilizing the light interference phenomenon and the film absorption phenomenon. Oxide, nitride or oxynitride films can be used for undercoat and overcoat.

It can effectively block moisture and oxygen in the air from diffusing into the transparent conductive film of the present invention, or alkali ions such as sodium in the substrate glass diffuse into the transparent conductive film of the present invention. because it can effectively block, S i O _x film, S i New _chi film, such as S i 0 N film is preferable.

In manufacturing targets, gallium oxide and indium oxide act as sintering aids when sintering tin oxide, the main component. At this time, gallium oxide and indium oxide strengthen each other's action. Gallium oxide and indium oxide also serve as additives for imparting conductivity to the target. Also in this case, the gallium oxide and the indium oxide reinforce each other's action and lower the resistance.

Further, in the transparent conductive film of the present invention, as in the case of the target, gallium oxide and indium oxide serve as additives for imparting conductivity to the film. In this case as well, gallium oxide and indium oxide strengthen each other's action and lower the resistance. In addition, gallium oxide and zinc oxide work to make the film amorphous by the effect of impurities. It lowers the resistance of the transparent conductive film and the target of the present invention. Also, oxides of the elements 3a, 4a and 5a act as sintering aids. In addition, since the transparent conductive film of the present invention has a function of strengthening the bond, it works to enhance the scratch resistance.

Example ·

In the following, Examples 1 to 26 and Examples 30 to 31 correspond to Examples, and Examples 27 to 29 correspond to Comparative Examples.

(Examples 1 to 15)

G a ₂ 0 ₃ powder was prepared I n ₂ 0 ₃ powder and S n0 ₂ powder, these powders in the proportions indicated in Table 1, were mixed in a dry ball mill. The target compositions shown in Table 1 were calculated from the weighed values of each raw material powder. In addition, the composition of the sintered body was measured by the ICP method (inductively coupled plasma emission spectroscopy), and it was confirmed that the composition matched the composition calculated from the weighed value of the raw material powder. The same applies to the following.

The average particle size of the powder used was, G a ₂ 0 ₃ powder, I n ₂ 0 ₃ powder and S n 0 ₂ powder each 2. 0〃M, 0. 8〃M and 1.1 0〃M met Was. These average particle diameters were measured with a microphone mouth track particle size analyzer manufactured by Nikkiso Co., Ltd.

This mixed powder is filled in a rubber mold, pressed with a CIP device, and then in air.

Firing was performed at a temperature of 1500 ° C, an atmospheric pressure, and a holding time of 2 hours. Table 1 shows the density and specific resistance of this sintered body. The density was measured by the Archimedes method. The specific resistance is 3 X 3 X

A 30 mm square sample was cut out and measured by a four-terminal method.

Next, the above-mentioned sintered body was cut into a size of 6 inches in diameter and 5 mm in thickness to prepare a target (hereinafter referred to as a GIT target).

Using these various GIT targets, using the magneto port down DC sputtering _{_{apparatus, G a 2 0 3 - I}} n 2 0 3 one S n 0 ₂ based transparent conductive film (hereinafter, referred to as GIT film) formed the film, applied power: 50 0 W, introduced gas: a r- C 0 ₂ mixed gas (a r + C 0 ₂ 1 00 volume ^_0/0 as C0 ₂ 3 0 vol ^_0/0, the total flow rate 5 0 sccm), ^{pressure: 4 X 1 0- 3 T orr} , substrate temperature was carried out in a non-heated condition. The board has a

—A lime glass substrate (hereinafter simply referred to as a glass substrate) was used. The film thickness is approximately

It was performed so as to be 100 nm.

In Examples 1 to 15, the optimal values of CO and concentration were found to be 10 to 50% by volume ( It was the introduction ratio of C0 ₂ to the sum of A r and C0 ₂ gas). Note that the Example 1 to 1-5 in Table 2, the representative value in the form of the C_〇 _2: shows the experimental results in the case of 3 0% by volume. Table 2 shows the specific resistance and transmittance of the various GIT films obtained.

The film compositions in Table 2 were measured by the ICP method. The composition of the target and the composition of the GIT film almost matched.

The film was identified using an X-ray diffractometer. In all of Examples 1 to 15, the X-ray diffraction pattern was flat and amorphous. FIG. 1 shows an X-ray diffraction pattern of the GIT film obtained in Example 2.

(Example 16: L 9)

Was also examined S b ₂ 0 ₅ powder or T e 0 ₂ powder was added system. The mixing ratio of the powder is as shown in Table 1.

A target was prepared in the same manner as in Example 1. Table 1 shows the density and specific resistance of this sintered body (target).

Film formation was performed under the same conditions as in Example 1 using a magnetron DC sputtering apparatus. Table 2 shows the composition, specific resistance, and transmittance of the film at this time.

The film compositions in Table 2 were measured by the ICP method. Comparing the film composition with the target composition, the content of Sb0— and TeO, in the film was decreasing.

The film was identified using an X-ray diffractometer. All of the films of Examples 16 to 19 had flat X-ray diffraction patterns and were amorphous.

(Example 20 to 26)

Y ₂ O ₃ , La ₂ O ₃ , Ce 0 ₂ , Pr ₆₀ , i, d, 0 Ti 0 ₉ , N b „0 _r as 3 a, 4 a and 5 a elements Table 1 shows the mixing ratio of the powders.

Under the same conditions as in Example 1, a film was formed using a magnetron DC sputtering apparatus. Table 2 shows the composition, specific resistance, and transmittance of the film at this time.

The film was identified using an X-ray diffractometer. All of the films of Examples 20 to 26 were amorphous by X-ray diffraction and flat in the turn. (Example 27 to 28)

G a ₂ 0 ₃ powder was prepared I n ₂ 0 ₃ powder and S n 0 ₂ powder, these powders in the proportions indicated in Table 1, were mixed in a dry ball mill.

In the same manner as in Example 1, a target was produced. Table 1 shows the density and specific resistance of this sintered body (target).

Example 1 and the same conditions (however, the sputtering gas is set to A r -◦ ₂ mixed gas

The proportion of oxygen was 3% by volume. This is because the preliminary experiments have shown that the ratio of oxygen that forms a low-resistance and transparent film is 3% by volume. Other conditions were the same as in Example 1), and a film was formed using a magnetron DC sputtering apparatus. Table 2 shows the composition, specific resistance, and transmittance of the transparent conductive film at this time.

Table 2 shows the specific resistance and transmittance of the obtained various transparent conductive films.

(Example 2 9)

I n ₂ 0 ₃ - were also examined S n 0 ₂ powder system. The mixing ratio of the powder is as shown in Table 1.

The target of this composition had high resistance and could not perform DC sputtering. Therefore, film formation was performed using a magnetron RF sputtering apparatus. The conditions other than the power supply were the same as in Example 27. Table 2 shows the specific resistance and transmittance of the film at this time. The specific resistance was higher than in Examples 1-26.

(Durability test)

In order to examine the acid resistance of the obtained transparent conductive film, each of the films of Examples 1 to 29 was left in a 5 wt% hydrochloric acid aqueous solution at room temperature for 2 hours. As a result, no erosion of the membrane and no change in resistance were observed for any of the membranes of Examples 1 to 26. A similar test was conducted for a 5 wt% sulfuric acid aqueous solution. No resistance change was observed.

The resistance of the film of Example 28 was increased by 20% and 10%, respectively, in the hydrochloric acid resistance test and the sulfuric acid resistance test.

The rate of change in resistance (·%) was determined by the following equation: Rate of change in resistance (%) = ((resistance after experiment) Z (initial resistance)-1) X 100.

In addition, in order to examine the alkali resistance, the films of Examples 1 to 29 were each left in a 5 wt% aqueous sodium hydroxide solution at 80 ° C. for 30 minutes. As a result, no erosion was observed for any of the membranes of Examples 1 to 26. The resistance change of each of the films of Examples 1 to 26 was as small as 0 to + 5% or less. The film of Example 27 had a 45% increase in resistance. The film of Example 28 had a 70% increase in resistance.

Further, in order to examine the hydrofluoric acid resistance, the films of Examples 1 to 29 were each left in a mixed aqueous solution of 2 wt% HF + 2 wt% nitric acid at room temperature for 30 minutes. As a result, no erosion of the membrane and no change in resistance were observed for any of the membranes of Examples 1 to 26. The membranes of Examples 27 and 28 all dissolved.

Further, in order to examine the moisture resistance, the films of Examples 1 to 29 were each left for 150 hours in an atmosphere at a temperature of 40 ° C. and a relative humidity of 90%. As a result, the resistance change of each of the films of Examples 1 to 26 was as small as ± 2% or less. The film of Example 28 had a 10% increase in resistance in moisture resistance.

In addition, in order to examine the resistance of the obtained transparent conductive film to CF ₄ gas, Examples 1 to

An etching test using CF ₄ gas was performed on each of the 29 films using a sputter etching apparatus. RF power: 200 W, introduced gas: CF ₄ (20 sccm)

Pressure: 1 0- ² T 0 rr, was carried out under conditions of processing time 3 0 minutes. As a result, Examples 1-2

All of the films 6 were not etched and had high resistance to CF ₄ gas. Also, the films of Examples 27 and 28 were all etched. The film of Example 29 was not etched.

In addition, in order to examine the scratch resistance of the obtained transparent conductive film, a sand erasing rubber (a type eraser TYPE 48—1005 mm diameter manufactured by Plus Co., Ltd.) was used for each of the films of Examples 1 to 29. The test was performed under the following conditions: load: 500 g, speed: 50 mm / min, number of times: 5 reciprocations. Evaluation: A: almost no damage, B: same damage as glass Nikure, C: Slightly damaged compared to glass, D: Severely damaged. The transparent conductive films of Examples 1 to 19 were ranked B, and the transparent conductive films of Examples 20 to 26 were ranked A, indicating that they exhibited high scratch resistance. The films of Examples 27 and 28 were ranked C. The film of Example 29 had a D rank.

Table 2 summarizes these results.

(Example 30)

The GIT film obtained in Example 2 was heat-treated in air at 250 ° C. for 30 minutes. As a result, the specific resistance was reduced to 1.8 × 10 ³ Ωcm. The visible light transmittance was unchanged at 82%. In addition, the GIT film obtained in Example 2 was set to N. During,

Heat treatment was performed at 500 ° C. for 30 minutes. As a result, the specific resistance was reduced to ^{1. 3 X 1 0- 3 Ω} cm. The visible light transmittance was unchanged and was 82%.

(Example 3 1)

A GIT film was formed in the same manner as in Example 2 except that the geometric film thickness of the GIT film was set to 150 nm.

Next, the electrode and the electrode take-out part were printed on the GIT film by a screen printing method, and baked at 300 ° C. After that, a lead wire was soldered to the electrode take-out part.

Next, a glass substrate having the same dimensions was prepared, and the glass substrate and the glass substrate on which the GIT film and the like had been formed were sealed with a sealant via a spacer to form a double-layer glass.

The visible light transmittance of the produced double-glazed glass was 80%. The color tone was neutral. When the resistance between the bus bar and the electrode was measured with a lead wire that penetrated the sealant and was taken out, it was 135 Ω. When a voltage of 32 V was applied between the bus bars to conduct a current test, the resistance value and appearance did not change even after 6 weeks, and were constant. As described above, the double-layer glass functioned well as electrothermal glass.

Industrial applicability

According to the present invention, a tin oxide-based transparent conductive film having excellent chemical resistance can be obtained. Further, since the transparent conductive film obtained by the present invention is amorphous, there is no unevenness on the surface, Since it is smooth, it has excellent abrasion resistance and is conductive, so that it can be used as an overcoat of an insulating material to have an effect as a highly durable antistatic film. In particular, since a transparent film can be obtained without heating the substrate, it can be used for an antistatic film having a protective film function such as a plastic film.

In addition, the target of the present invention is conductive and can perform DC sputtering at a high film formation rate. In addition, the target is dense and can be sputtered by a stable discharge.

Claims

1) Scope of billing

1. A transparent conductive film of tin oxide containing gallium and indium, converting the Gallium to G a ₂ 0 _3, the Lee indium I n ₂ _0: in terms of _I, tin S eta 0 when converted into _2,. G a ₂ 0 ₃ and I n ₂ 0 ₃ and S n 0 with respect to the total amount of _2, 0.1 1 of Gariu beam in G a ₂ 0 "terms 3 0 mole ^_0/0 Contained, and the insulator was In ₂₀

A transparent conductive film containing 0.1 to 30 mol% in terms of 3 in conversion.

2. The content of the gully um is a 1-1 5 mole ^_0/0 G a ₂ 0 ₃ in terms of, and the content of the in-Jiumu is from 1 1 to 5 mol% in I n ₂ 0 ₃ in terms of Claim 1

3. The transparent conductive film according to claim 1, which contains antimony and phosphorus or tellurium.

4. The transparent conductive film according to claim 1, comprising at least one metal selected from the group consisting of Group 3 (including lanthanides, excluding actinides), Group 4 and Group 5 in the long-period periodic table. .

5. A substrate with a transparent conductive film, wherein the transparent conductive film according to claim 1 is formed on the substrate.

6. A Supattari Ngutage' capital of tin oxide containing gallium and indium, converting the gallium G a Li 0 _3, converts the Lee indium I n, 0, a, a tin S n 0 ₂ when converted, for the total amount of G a ₂ 0 ₃ and I n ₂ 0 ₃ and S n 0 _2, gallium containing from 0.1 to 3 0 mol% G a ₂ 0 ₃ in terms of, and indicator © sputtering Taringutage' you want to, characterized in that 0.1 to 3 0 mol ^_0/0 containing beam at I n ₂ 0 ₃ basis.

7. content of gully um is in 1-1 5 mole ^_0/0 G a ₂ 〇 ₃ basis, and the content of Injiu arm is in 1-1 5 mole ^_0/0 I n ₂ 0 ₃ basis 7. The sputtering target according to claim 6, wherein:

8. The sputtering target according to claim 6, comprising antimony and / or tellurium.

9. The snowboard according to claim 6, comprising at least one metal selected from the group consisting of Group 3 (including lanthanoids, not including lactinoids), Group 4 and Group 5 in the long-periodic table. Tatting target.